1 Identification Information

1.1 Citation Information:

8.1 Originator: United States Geological Survey

8.2 Publication Date: 1984

8.4 Title:

Bathymetric map of the Chukchi Sea

8.7.1 Series Name: Miscellaneous Investigations Series

8.7.2 Issue Identification: Map I-1182-D

8.8.2 Publisher:

United States Geological Survey

8.9 Other Citation Details:

Hill, E. R., A. Grantz, S. D. May, and M. Smith. 1984. Bathymetric map of the Chukchi Sea. U.S. Geological Survey, Misc. Inves. Series I-1182-D.

1.2 Description

1.2.1 Abstract:

Bathymetric contours were generated from soundings collected during geophysical surveys conducted by the USGS from 1969 to 1982, and supplemented by data from other sources. The region covered by the map is the Chukchi Sea from the Bering Strait north to the Arctic Ocean, and Point Barrow, Alaska west to Herald Island, Russia. The map stops just east of Wrangel Island, Russia. Bathymetry is in meters, including 10 meter contour intervals from 10 to 100 meters, and 100 meter contour intervals at depths greater than 100 meters.

1.2.2 Purpose:

The bathymetric map was produced to provide a base for displaying further geophysical and biological data. It was not intended to be used for navigation.

1.2.3 Supplemental Information:

competed coverage stored on ASC workstation GULO in the following directory: /gulo1/ecosys/bathy/final. The coverage is titled CHUKBATH_3GEO (chuk=chukchi sea, bath=bathymetry, 3=polygon topology, geo=geographic projection).

1.3 Time Period Of Content

1.3.1 Currentness Reference: Publication Date

1.4 Status

1.4.1 Progress: Complete

1.4.2 Maintenance and Update Frequency: None Planned

1.5 Geographic Extent

1.5.2 Bounding Rectangle Coordinates

1.5.2.1 West Bounding Coordinate: -176

1.5.2.2 East Bounding Coordinate: -153

1.5.2.3 North Bounding Coordinate: 74.5

1.5.2.4 South Bounding Coordinate: 65.5

1.6 Keywords

1.6.1.1 Theme Keyword Thesaurus: None

1.6.1.2 Theme Keyword: Bathymetry

1.6.2.1 Place Keyword Thesaurus: None

1.6.2.2 Place Keyword: Chukchi Sea

1.6.2.2 Place Keyword: Arctic Ocean

1.6.2.2 Place Keyword: Northwest Alaska

1.6.2.2 Place Keyword: Northeast Russia

1.6.3.1 Stratum Keyword Thesaurus: None

1.6.4.1 Temporal Keyword Thesaurus: None

1.10 Point of Contact

10.2 Contact Organization Primary

10.1.2 Contact Organization: Alaska Science Center, Marine and Fresh Water Ecology Branch

10.4 Contact Address

10.4.1 Address Type: Mailing and Physical Address

10.4.2 Address: Biological Resources Division, U.S. Geological Survey

10.4.2 Address: 1011 E. Tudor Road

10.4.3 City: Anchorage

10.4.4 State or Province: Alaska

10.4.5 Postal Code: 99503

10.4.6 Country: USA

10.5 Contact Voice Telephone: (907) 786-3512

10.7 Contact Facsimile Telephone: (907) 786-3636

10.9 Hours of Service: 8:00 a.m. to 4:00 p.m. Monday Through Friday

10.10 Contact Instructions: None

1.14 Native Data Set Environment: UNIX-ARC/INFO

1.15 Cross Reference

8.1 Originator: United States Geological Survey

8.2 Publication Date: 1988

8.4 Title:

Bathymetric Map of the Bowers Basin and Aleutian Basin east of the U.S.-U.S.S.R. 1867 Convention Line, Bering Sea

8.6 Data Presentation Form: Map

8.7.1 Series Name: Open File Report

8.7.2 Issue Identification: 89-548

8.8.1 Publication Place:

U.S. Geological Survey, Menlo Park, California

8.8.2 Publisher:

United States Geological Survey

8.9 Other Citation Details:

Hall, R.K., H.A. Karl, P.R. Carlson, A.K. Cooper, J.V. Gardner, R.E. Hunter, M.S. Marlow, and A.J. Stevenson. 1989. Bathymetric map of the Aleutian Basin and Bowers Basin east of the U.S.-U.S.S.R. 1867 Convention Line, Bering Sea. U. S. Geological Survey Open-File Report 89-548, 6 pp, 1 map, scale 1:2,000,000.

8.10 Online Linkage: http://walrus.wr.usgs.gov

8.1 Originator: United States Geological Survey

8.2 Publication Date: 1976

8.4 Title:

Plate 1. Topographic and Bathymetric map of the Northern Bering Sea Region

8.7.1 Series Name: Geological Survey Professional Paper

8.7.2 Issue Identification: 759-B

8.8.1 Publication Place:

Washington D.C.

8.8.2 Publisher:

U. S. Government Printing Office

8.9 Other Citation Details:

Hopkins, D. M., C. H. Nelson, R. B. Perry, and T. R. Alpha. 1976. Physiographic subdivisions of the Chirikov Basin, Northern Bering Sea (studies on the marine geology of the Bering Sea). Geological Survey Professional Paper 759-B. U.S. Government Printing Office. 7pp. 3 plates.

8.1 Originator: United States Geological Survey

8.2 Publication Date: 1976

8.4 Title:

Bathymetric Map of the Chukchi Sea and Arctic Ocean & Bathymetric Map of the Aleutian Trench and Bering Sea

8.7.1 Series Name: Open File Report

8.7.2 Issue Identification: 76-821 and 76-823

8.8.1 Publication Place:

Washington D.C.

8.8.2 Publisher:

U.S. Geological Survey

8.9 Other Citation Details:

Schumacher, G. M. 1976. Bathymetric map of the Chukchi Sea and Arctic Ocean. USGS Open File Report 76-823. Schumacher, G. M. 1976. Bathymetric map of the Aleutian Trench and Bering Sea. USGS Open File Report 76-821.

2 Data Quality Information

2.1 Attribute Accuracy

2.1.1 Attribute Accuracy Report:

Attribute accuracy was tested by manually comparing hard copy plots to the source map.

2.2 Logical Consistency Report:

All polygon features are checked for topology using Arc/INFO software. Each polygon begins and ends with a node feature. All nodes are checked for errors so that there are no dangling features. There are no duplicate lines or polygons. All nodes will snap together and close polygons based on a specified tolerance. If the node is not within the tolerance it is adjusted manually. The tests for logical consistency are performed in Arc/INFO.

2.3 Completeness Report:

Contours were digitized at 10 meter intervals from 10 meters to 100 meters. Several intermediate contours (e.g. 5, 15, 25, etc.) were not digitized, many were dangling arcs which could not be used to build polygons. From 100 meters to 1,000 meters contours were digitized at 100 meter intervals, same as the resolution on the source map. Beyond 1,000 meters, contours were digitized at 1,000 meter intervals, while the map resolution contained 100 meter intervals. A 1:2,000,00 scale coastline (source = digital chart of the world) was added to the coverage to provide a land reference.

2.4 Positional Accuracy

2.4.1 Horizontal Positional Accuracy

2.4.1.1 Horizontal Positional Accuracy Report:

Horizontal positional accuracy was tested using Arc/INFO's RMS errors generated when the digitized map is converted from table inches to real world coordinates. RMS errors for this map ranged from 0.02 to 0.09 which are very poor. Reasons for the high errors may include lack of projection information provided on the source map, errors described in the documentation with the source map, creases in the paper, and/or characteristics of paper media. However, the map accurately overlays plots of the Russian and Alaskan coastlines, so we assume that overall error is minimal (see process description below).

2.5.2 Source Information

2.5.2.1 Source Citation:

8.1 Originator: United States Geological Survey

8.2 Publication Date: 1984

8.4 Title:

Bathymetric map of the Chukchi Sea

8.7.1 Series Name: Miscellaneous Investigations Series

8.7.2 Issue Identification: Map I-1182-D

8.8.2 Publisher:

United States Geological Survey

8.9 Other Citation Details:

Hill, E. R., A. Grantz, S. D. May, and M. Smith. 1984. Bathymetric map of the Chukchi Sea. U.S. Geological Survey, Misc. Inves. Series I-1182-D.

2.5.2.2 Source Scale Denominator: 1000000

2.5.2.3 Type Of Source Media: Paper

2.5.2.4 Source Time Period Of Content:

2.5.2.4.1 Source Currentness Reference: Publication Date

2.5.3 Process Step

2.5.3.1 Process Description:

The source map was in Polar Stereographic projection, scale 1:1,000,000 at latitude 72 00 N, no central meridian was provided with the source map, and none could be determined. A tic base from a previous digitizing effort of the same map was used because it provided the best accuracy (history of the existing tic base, and why it is relatively accurate, is not available). The source map was hand digitized and registered into Albers 154 projection to match the tic base. After the map was digitized, the digital chart of the world coastline (1:2,000,000 scale) was added to provide a land reference and complete the near shore polygons. Processing tolerances were: weed 70 meters, grain 70 meters, dangle 0.1 meters, and fuzzy 0.1 meters. Note that the tolerances are listed in meters and the coverage is in geographic. THESE TOLERANCES SHOULD BE SPECIFIED IN ANY FUTURE BUILD OR CLEAN TO MAINTAIN THE INTEGRITY OF THE COVERAGE.

2.5.3.3 Process Date: 199609

2.5.3.6 Process Contact:

10.2 Contact Organization Primary

10.1.2 Contact Organization: Alaska Science Center, Marine and Fresh Water Ecology Branch

10.4 Contact Address

10.4.1 Address Type: Mailing and Physical Address

10.4.2 Address: Biological Resources Division, U.S. Geological Survey

10.4.2 Address: 1011 E. Tudor Road

10.4.3 City: Anchorage

10.4.4 State or Province: Alaska

10.4.5 Postal Code: 99503

10.4.6 Country: USA

10.5 Contact Voice Telephone: (907) 786-3512

10.7 Contact Facsimile Telephone: (907) 786-3636

10.9 Hours of Service: 8:00 a.m. to 4:00 p.m. Monday Through Friday

10.10 Contact Instructions: None

3 Spatial Data Organization Information

3.1 Indirect Spatial Reference:

bathymetric contours

3.2 Direct Spatial Reference Method: Vector

3.3 Point and Vector Object Information

3.3.1.1 SDTS Point and Vector Object Type: arcs

3.3.1.2 Point and Vector Object Count: 315

3.3.1.1 SDTS Point and Vector Object Type: polygons

3.3.1.2 Point and Vector Object Count: 94

3.3.1.1 SDTS Point and Vector Object Type: label points

3.3.1.2 Point and Vector Object Count: 94

4 Spatial Reference Information

4.1 Horizontal Coordinate System Definition

4.1.2 Planar

4.1.2.1.1 Map Projection Name: latitude/longitude geographic

4.1.4.1 Horizontal Datum Name: North American Datum of 1927

4.1.4.2 Ellipsoid Name: Clarke 1866

4.2.2.1 Depth Datum Name: No Correction

4.2.2.2 Depth Resolution: 10

4.2.2.2 Depth Resolution: 100

4.2.2.3 Depth Distance Units: meters

4.2.2.4 Depth Encoding Method: Attribute Values

5 Entity and Attribute Information

5.1 Detailed Description

5.1.2 Attribute

5.1.2.1 Attribute Label: mid-depth

5.1.2.2 Attribute Definition:

Polygon attribute calculated as the mid-point between bounding arcs, eg mid-depth between 10 m and 20 m isobaths equals 15 m; and between 2,000 and 3,000 m isobaths equals 2,500 m. Where a bathymetric contour was an "island" and there was no depth information inside the "island", the mid-depth was coded as the bounding contour's depth.

5.1.2.4.2 Range Domain 5

5.1.2.4.2.1 Range Domain Minimum: 5

5.1.2.4.2.2 Range Domain Maximum: 3500

5.1.2.5 Attribute Units Of Measurement: meters

5.1.2.6 Attribute Measurement Resolution: 10

5.1.2 Attribute

5.1.2.1 Attribute Label: depth

5.1.2.2 Attribute Definition:

Depth in meters below sea level for each contour. Used to calculate mid-depth attribute.

5.1.2.4.2 Range Domain 10

5.1.2.4.2.1 Range Domain Minimum: 10

5.1.2.4.2.2 Range Domain Maximum: 3,000

5.1.2.5 Attribute Units Of Measurement: meters

5.1.2.6 Attribute Measurement Resolution: 10

5.1.2 Attribute

5.1.2.1 Attribute Label: class

5.1.2.2 Attribute Definition:

class = 0 for digitized bathymetric contours; class = 8 for arcs that were added to close polygons; class = 9 for arcs representing the Russian and US coastlines. Class 8 arcs occurred in three locations: (1) adding arcs to close polygons was necessary in several places where contour lines on the source map ended because adjoining contours were too close (particularly in the Barrow Canyon area); (2) the 10 m contour on the source map ended and then restarted near the tip of Point Hope, Alaska, a class 9 arc was added to complete the 10 m contour in that location; (3) a box was placed around the coverage to define the boundary of the map.

5.1.2.4.2 Range Domain 0

5.1.2.4.2.1 Range Domain Minimum: 0

5.1.2.4.2.2 Range Domain Maximum: 9

5.2 Overview Description

5.2.1 Entity and Attribute Overview:

The coverage contains two attributes pertinant for data analysis and display (depth and mid-depth), and one attribute that specifies line type (class). Depth is an arc attribute (.aat) that specifies the ocean depth at each contour in meters. Mid-depth is a polygon attribute (.pat) calculated from the depth values of each polygon's bounding contours (e.g. a polygon with bounding contours of 30 m and 40 m would be 35 m). Class displays the type of line, 0 for digitized bathymetric contours, 8 for arcs added to close polygons, and 9 for the coastline.

6 Distribution Information

6.1 Distributor

10.2 Contact Organization Primary

10.1.2 Contact Organization: Alaska Science Center, Marine and Fresh Water Ecology Branch

10.4 Contact Address

10.4.1 Address Type: Mailing and Physical Address

10.4.2 Address: Biological Resources Division, U.S. Geological Survey

10.4.2 Address: 1011 E. Tudor Road

10.4.3 City: Anchorage

10.4.4 State or Province: Alaska

10.4.5 Postal Code: 99503

10.4.6 Country: USA

10.5 Contact Voice Telephone: (907) 786-3512

10.7 Contact Facsimile Telephone: (907) 786-3636

10.9 Hours of Service: 8:00 a.m. to 4:00 p.m. Monday Through Friday

10.10 Contact Instructions: None

6.3 Distribution Liability:

Although these data have been processed successfully on a computer system at the Alaska Science Center, Biological Resources Division, US Geological Survey, no warranty expressed or implied is made regarding the accuracy or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data. It is strongly recommended that these data are directly acquired from an Alaska Science Center server, and not indirectly through other sources which may have changed the data in some way. It is also strongly recommended that careful attention be paid to the contents of the metadata file associated with these data. The Alaska Science Center shall not be held liable for improper or incorrect use of the data described and/or contained herein.

6.4 Standard Order Process

6.4.1 Non-Digital Form: map. Miscellaneous Investigations I-1182-D

6.4.3 Fees: contact USGS for fee information

6.4.4 Ordering Instructions: USGS Information Services, Box 25046, MS 507, Denver, CO 80225 USA [303-202-4210] or USGS National Mapping Division, Map Sales, 4230 University Dr., Anchorage, AK 99508 USA [907-786-7011].

6.4 Standard Order Process

6.4.2 Digital Form

6.4.2.1.1 Format Name: ARC/INFO

6.4.2.1.2 Format Version Number: Version 7.1

6.4.2.1.6 File Decompression Technique: Arc Export (full compression

6.4.2.1.7 Transfer Size: 1304986

6.4.2.2 Digital Transfer Option

6.4.2.2.1.2 Access Instructions: FTP:ftp.asc.nbs.gov, access ftp site as anonymous, change directory to OUTGOING/BATHY, transfer under ASCII mode (type ascii), get CHUKBATH_3GEO.E00

6.4.3 Fees: none

7 Metadata Reference Information

7.1 Metadata Date: 19961001

7.4 Metadata Contact:

10.2 Contact Organization Primary

10.1.2 Contact Organization: Alaska Science Center, Marine and Fresh Water Ecology Branch

10.4 Contact Address

10.4.1 Address Type: Mailing and Physical Address

10.4.2 Address: Biological Resources Division, U.S. Geological Survey

10.4.2 Address: 1011 E. Tudor Road

10.4.3 City: Anchorage

10.4.4 State or Province: Alaska

10.4.5 Postal Code: 99503

10.4.6 Country: USA

10.5 Contact Voice Telephone: (907) 786-3512

10.7 Contact Facsimile Telephone: (907) 786-3636

10.9 Hours of Service: 8:00 a.m. to 4:00 p.m. Monday Through Friday

10.10 Contact Instructions: None

7.5 Metadata Standard Name: FGDC Content Standards For Digital Geospatial Metadata

7.6 Metadata Standard Version: June 8, 1994

Please send comments or questions about the content of this page to Chad Jay or Tony Fischbach

Please send comments or questions about this web page to: mwhalen@usgs.gov